So I had a (fresh water eel) given to me he was just a little guy I researched him and found out he's brackish so I changed my tank setup to better suit him but other then the basics I know little about cool brackish fish. I have a 55 gallon tank that's all earl's that's my eel. He seems happy he eats good but I need some good ideas for tank mates I would prefer smaller fish with him but I know not to small and no puffers